Washing machine drum sizes

Last updated on March 3rd, 2017

Washing machine drum sizes were the same for decades, but now we have several to choose from. You would think the biggest is the best, but not necessarily. Back in 1976 when I first started repairing washing machines, all the drums were about 4 &half; kg. By today’s standards they were painfully small.

What are the advantages for larger drum capacities?

The first obvious advantage is that you can fit some large items in the machine that you would otherwise be unable to wash. The biggest advantage is that you can wash a lot more laundry at a time, and reduce wear and tear on the machine as well as running costs. However, as described below, many people struggle to utilise a large drum capacity properly and therefore do not really save any money.

Why are there so many different sizes?

As with most products, manufacturers want to offer as many variations of their product as possible in order to have a big range and appeal to everyone’s wants and price range. This is true regardless of whether the different options they create are necessary or not. Large capacity washing machine drums can be inappropriate for some people as described below, but they’ve become very popular.

We definitely needed bigger drums

Someone eventually decided to have a go at making drum capacity bigger. To be fair it was a welcome move. They managed to get the size up to 5 Kg. A paltry but welcome increase with no downsides as far as I could see. Drum sizes remained at around 5Kg for many years after. At the end of the day there was no room for anything bigger really. But eventually someone managed to make one at 6Kg, which was another welcome increase with no real noticeable downsides.

Eventually they realised that not only could they charge more for a bigger drum but they could also even persuade people to upgrade to a bigger one. They slowly went up to 7Kg, 8Kg, 9Kg 10Kg and beyond. So bearing in mind there is very little room for making the actual washing machine much bigger – how did they do it and what are the down sides?

What are the disadvantages of bigger drums?

If you think about it, apart from depth, washing machines are still virtually the same size as they always were. They are only slightly bigger – yet some have greatly increased drums. This is achieved by increasing the size the main drum, which decreases the space for all other parts including the space between the outer drum and the sides of the cabinet. If there’s less room for the outer drum to move before hitting and dinting the cabinet then stopping the spinning of loads that even hint at being out of balance may be employed to compensate. This can mean problems with loads not spinning at all or not being spun at full speed (Washing machine won’t spin just one item or very small load)

Much bigger drums also need bigger doors and a bigger door glass. It is at least theoretically possible that larger door glass could be relevant in a safety issue where a slow but steady trickle of people are reporting that their door glass has exploded (Washing machine exploding door glass danger). Another potential disadvantage is that many people might assume or believe that they are more economical, but they can be less economical for many people as explained below.

Are bigger drums more economical?

A bigger drum requires more water, more detergent, and will presumably need slightly more energy to turn it. They only use less of anything over a given time period if the larger drum capacity has allowed you to do less loads. If you buy a large capacity drum but don’t increase your wash load you will more likely be wasting – not saving – money. Using a washing machine less times each week means less electricity, less water, less detergent and less wear and tear on the machine. If you don’t regularly use the extra capacity then you have paid a fair bit more for the washing machine just so that every so often you could wash something quite large. This may very well be perfectly acceptable of course. It just makes sense to properly utilise the drum capacity you have bought.

Do you need a large drum capacity?

I’ve read reports that the average wash load in the UK is only around 3 to 4 Kg – therefore it seems likely that a large drum capacity will be less economical to use for many – if not most – people. So if you have large items that you want to wash and think it is worth paying extra for a larger drum capacity and even potentially using more resources during normal wash loads then you may be happy to buy a washing machine with a big drum.

If on the other hand you are interested in a large drum capacity because you think it is more economical than just make sure that you are going to use that extra capacity on a regular basis. If you are not going to put a fair bit more laundry inside on most washes then it can’t really be economic. In such cases consider a more modest drum size such as 6 kg. At the end of the day it is probably better if everybody had larger drum capacities as long as they use the space.